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Sam K, Zabbey N, Vincent-Akpu IF, Komi G, Onyagbodor PO, Babatunde BB. Socio-economic baseline for oil-impacted communities in Ogoniland: towards a restoration framework in Niger Delta, Nigeria. Environ Sci Pollut Res Int 2024; 31:25671-25687. [PMID: 38483715 PMCID: PMC11024028 DOI: 10.1007/s11356-024-32805-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 03/03/2024] [Indexed: 04/19/2024]
Abstract
This study documents the socio-economic baselines in selected oil-impacted communities prior to the commencement of the Ogoni clean-up and restoration project. Adopting mixed approach consisting of semi-structured interviews, focus group discussions (FGDs), key informant interviews (KIIs), and household surveys, we surveyed the pre-remediation socio-economic conditions in the Ogoniland communities between July 2018 and March 2019. Results indicated that almost all respondents (99.6%) agreed that the smell of petroleum products or crude oil was evident in the air they breathed even as there were visible black particles (soot) in the respondents' nostrils, on their clothes, and in water. The respondents described the ambient air as smoky and choked with an offensive smell. The household waters were smelly, brownish, or oily, and most respondents (76%) cannot afford to treat their water. Forty-two percent of the respondents who relied on fishing and farming for a living sought for alternative means of subsistence and acknowledged that oil pollution caused stunted growth and low crop yield. The majority of respondents (91%) reported falling fish catches, while the fish caught smell and taste of oil, lowering their market value and posing a potential health risk to consumers. It is evident that oil pollution has impacted the socio-ecological values and sustainable livelihood in Ogoniland. This study provides baseline data for monitoring post-remediation socio-economic improvements in Ogoniland. It also highlights areas of urgent intervention to improve livelihood, and access to basic amenities (e.g., potable drinking water), waste management infrastructure, and statutory policy changes for sustainable development in Ogoniland.
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Affiliation(s)
- Kabari Sam
- School of Environment, Geography and Geoscience, University of Portsmouth, Burnaby Road, Portsmouth, PO1 3QL, UK.
- Department of Marine Environment and Pollution Control, Nigeria Maritime University Okerenkoko, Warri, Nigeria.
| | - Nenibarini Zabbey
- Department of Fisheries, Faculty of Agriculture, University of Port Harcourt, East-West Road, PMB 5323, Choba, Port Harcourt, Rivers State, Nigeria
- Environment and Conservation Unit, Centre for Environment, Human Rights and Development (CEHRD), D-Line, Port Harcourt, Rivers State, Nigeria
| | - Ijeoma Favour Vincent-Akpu
- Department of Animal and Environmental Biology, Faculty of Biological Sciences, University of Port Harcourt, PMB 5323, Choba, Port Harcourt, Rivers State, Nigeria
| | - Gentle Komi
- Department of Animal and Environmental Biology, Faculty of Biological Sciences, University of Port Harcourt, PMB 5323, Choba, Port Harcourt, Rivers State, Nigeria
| | - Peter Oghogho Onyagbodor
- Department of Animal and Environmental Biology, Faculty of Biological Sciences, University of Port Harcourt, PMB 5323, Choba, Port Harcourt, Rivers State, Nigeria
| | - Bolaji Bernard Babatunde
- Department of Animal and Environmental Biology, Faculty of Biological Sciences, University of Port Harcourt, PMB 5323, Choba, Port Harcourt, Rivers State, Nigeria
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Abdulai PM, Sam K, Onyena AP, Ezejiofor AN, Frazzoli C, Ekhator OC, Udom GJ, Frimpong CK, Nriagu J, Orisakwe OE. Persistent organic pollutants and heavy metals in Ghanaian environment: a systematic review of food safety implications. Environ Monit Assess 2024; 196:376. [PMID: 38492071 DOI: 10.1007/s10661-024-12500-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Accepted: 02/24/2024] [Indexed: 03/18/2024]
Abstract
Advances in industrial and technological innovations have led to significant socio-economic benefits, but with overwhelming negative impacts on the environment. These impacts include the infiltration of organic contaminants into soil, water, and air, posing a threat to the environment and public health. Polybrominated diphenyl ethers (PBDEs), heavy metals, and polycyclic aromatic hydrocarbons (PAHs) are increasingly released as waste, endangering the environment. In countries like Ghana, where regulations are weakly enforced, industrial waste is released uncontrollably, posing threats to public health, environmental integrity, and food systems. This study systematically evaluated existing literature on PBDEs, heavy metals, PAHs, and organic contaminant exposure in Ghana and proposes a roadmap for achieving food safety and protecting the environment and human health. The research identified high mobility of specific heavy metals and risks associated with PBDEs and PAHs in sediments, dumpsites, and various food items. Unregulated dumping of electronic waste with PBDEs raised environmental concerns. An integrated approach is needed to address the multifaceted impact of organic pollutants on public health and ecosystems. Urgent implementation of effective environmental management strategies and regulatory measures is crucial. The study proposed short- to mid-term priorities emphasising the need to foster collaboration and implementing global measures. The mid- to long-term strategy includes a national information surveillance system, local monitoring capacity development, and integrating land contamination controls with food safety legislation. These measures would mitigate risks, ensure sustainable practices, and improve overall food safety management in Ghana, serving as a model for regions facing similar challenges with diverse pollutants.
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Affiliation(s)
- Prosper Manu Abdulai
- African Centre of Excellence for Public Health and Toxicological Research (ACE-PUTOR), University of Port Harcourt, PMB, Port Harcourt, Choba, 5323, Nigeria
| | - Kabari Sam
- Department of Marine Environment and Pollution Control, Nigeria Maritime University, Okerenkoko, Nigeria
- School of the Environment, Geography and Geoscience, University of Portsmouth, University House, Winston Churchill Ave, Portsmouth, PO1 2UP, UK
| | - Amarachi Paschaline Onyena
- Department of Marine Environment and Pollution Control, Nigeria Maritime University, Okerenkoko, Nigeria
| | - Anthoneth Ndidi Ezejiofor
- African Centre of Excellence for Public Health and Toxicological Research (ACE-PUTOR), University of Port Harcourt, PMB, Port Harcourt, Choba, 5323, Nigeria
| | - Chiara Frazzoli
- Department for Cardiovascular, Endocrine-Metabolic Diseases, and Aging, Istituto Superiore Di Sanità, Rome, Italy
| | - Osazuwa Clinton Ekhator
- Department of Science Laboratory Technology, Faculty of Science, University of Benin, Benin City, Nigeria
| | - Godswill J Udom
- Department of Pharmacology and Toxicology, Federal University Oye-Ekiti, Oye-Ekiti, Nigeria
| | - Caleb Kesse Frimpong
- Department of Biochemistry and Biotechnology, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Jerome Nriagu
- Department of Environmental Health Sciences, School of Public Health, University of Michigan, Ann Arbor, MI, USA
| | - Orish Ebere Orisakwe
- African Centre of Excellence for Public Health and Toxicological Research (ACE-PUTOR), University of Port Harcourt, PMB, Port Harcourt, Choba, 5323, Nigeria.
- Advanced Research Centre, European University of Lefke, Lefke, Northern Cyprus, TR-10 Mersin, Turkey.
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Lee H, Sam K, Coulon F, De Gisi S, Notarnicola M, Labianca C. Recent developments and prospects of sustainable remediation treatments for major contaminants in soil: A review. Sci Total Environ 2024; 912:168769. [PMID: 38008308 DOI: 10.1016/j.scitotenv.2023.168769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 11/17/2023] [Accepted: 11/19/2023] [Indexed: 11/28/2023]
Abstract
Rapid industrialisation and urbanisation are contributing to the entry of emerging contaminants into the environment, posing a significant threat to soil health and quality. Therefore, several remediation technologies have been investigated and tested at a field scale to address the issue. However, these remediation technologies face challenges related to cost-effectiveness, environmental concerns, secondary pollution due to the generation of by-products, long-term pollution leaching risks, and social acceptance. Overcoming these constraints necessitates the implementation of sustainable remediation methodologies that prioritise approaches with minimal environmental ramifications and the most substantial net social and economic advantages. Hence, this review delves into diverse contaminants that threaten soil health and quality. Moreover, it outlines the research imperatives for advancing innovative remediation techniques and effective management strategies to tackle this concern. The review discusses a remediation treatment train approach that encourages resource recovery, strengthens the circular economy, and employs a Life Cycle Assessment (LCA) framework to assess the environmental impacts of different remediation strategies. Additionally, the study explores mechanisms to integrate sustainability principles into soil remediation practices. It underscores the necessity for a comprehensive and systematic approach that takes into account the economic, social, and environmental consequences of remediation methodologies in the development of sustainable solutions.
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Affiliation(s)
- H Lee
- College of Engineering and Physical Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - K Sam
- School of the Environment, Geography and Geoscience, University of Portsmouth, University House, Winston Churchill Ave, Portsmouth PO1 2UP, UK
| | - F Coulon
- School of Water, Energy and Environment, Cranfield University, Cranfield, Bedfordshire MK43 0AL, UK
| | - S De Gisi
- Department of Civil, Environmental, Land, Building Engineering and Chemistry (DICATECh), Polytechnic University of Bari, Via E. Orabona n. 4, 70125 Bari, Italy
| | - M Notarnicola
- Department of Civil, Environmental, Land, Building Engineering and Chemistry (DICATECh), Polytechnic University of Bari, Via E. Orabona n. 4, 70125 Bari, Italy
| | - C Labianca
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China; Arup, Level 5, Festival Walk, 80 Tat Chee Avenue, Kowloon Tong, Hong Kong, China.
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Sam K, Pegg S, Oladejo AO. Mining from the pipeline: Artisanal oil refining as a consequence of failed CSR policies in the Niger Delta. J Environ Manage 2024; 352:120038. [PMID: 38232589 DOI: 10.1016/j.jenvman.2024.120038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 12/29/2023] [Accepted: 12/29/2023] [Indexed: 01/19/2024]
Abstract
Oil production in the Niger Delta first attained global prominence after the 1995 hangings of Ken Saro-Wiwa and eight other Ogonis. In the face of horrible publicity and credible allegations that international oil companies were complicit in systematic human rights violations against local host communities, corporate social responsibility (CSR) was embraced. CSR in the Nigerian oil industry has evolved from non-existent to limited community development programs to today's Global Memorandum of Understanding model. Yet, concomitant with CSR's growth has been a devastating increase in artisanal oil refining or "bunkering." In this article, we do not focus on industrial scale bunkering, which clearly requires high-level political support. Instead, we focus on the growth of small-scale artisanal refining in the rural Niger Delta. We situate this sector's growth in failed government and CSR policies, highlight its devastating environmental impacts, and advocate a shift away from flawed and limited CSR to legal and regulated modular refineries that, with fewer negative developmental and environmental externalities, could serve as a vital source of job creation and wealth generation.
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Affiliation(s)
- Kabari Sam
- School of Environment, Geography and Geoscience, University of Portsmouth, Burnaby Road, Portsmouth, PO1 3QL, UK
| | - Scott Pegg
- Department of Political Science, Indiana University Indianapolis, 425 University Boulevard, Indianapolis, IN, 46202, USA.
| | - Abiodun Omotayo Oladejo
- Research Innovation and Development, Walter Sisulu University, Nelson Mandela Drive, Mthatha, Eastern Cape, South Africa
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Sam K, Zibima T. Inclusive Environmental Decision-making in a Developing Nation: Insights from the Ogoni Remediation Project, Niger Delta, Nigeria. Environ Manage 2024; 73:323-337. [PMID: 37770627 PMCID: PMC10847202 DOI: 10.1007/s00267-023-01885-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Accepted: 09/17/2023] [Indexed: 09/30/2023]
Abstract
Greater involvement of women is globally believed to enhance environmental management outcomes. Despite being disproportionately affected by environmental degradation primarily caused by oil spills in the Niger Delta region of Nigeria, women in the region are often excluded in environmental decision-making processes. Women involved in farming and fishing face increased vulnerability to contaminated land, food insecurity and conflicts driven by environmental degradation. Using a mixed approach, women, lawmakers, policymakers, regulators, civil society organizations, environmental management practitioners, and government agents responsible for environmental remediation were engaged through interviews, focus group discussions and questionnaires to examine women's inclusion in environmental decision-making and governance in the Ogoni contaminated land remediation project in the Niger Delta region of Nigeria. The results indicate that lack of trust and confidence in drivers of the environmental decision-making process could affect women's participation and involvement in environmental management. Although cultural beliefs and practices impede the participation of women in the region, their actual participation does not independently translate into inclusion in environmental decision-making due to limited capacity, confidence and trust in the process. Creating platforms for capacity building, developing gender policy, adapting appropriate communication strategies, initiating women networks and strengthening social cohesion could enhance women involvement in environmental decision-making in regions with similar cultural context to the Niger Delta region.
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Affiliation(s)
- Kabari Sam
- School of Environment, Geography and Geoscience, University of Portsmouth, Burnaby Road, Portsmouth, PO1 3QL, UK.
| | - Tubodenyefa Zibima
- Department of Political Science, Niger Delta University, Wilberforce Island, Bayelsa, Nigeria
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Azuazu IN, Sam K, Campo P, Coulon F. Challenges and opportunities for low-carbon remediation in the Niger Delta: Towards sustainable environmental management. Sci Total Environ 2023; 900:165739. [PMID: 37499826 DOI: 10.1016/j.scitotenv.2023.165739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Revised: 07/14/2023] [Accepted: 07/21/2023] [Indexed: 07/29/2023]
Abstract
There is increasing demand for low-carbon remediation strategies for reducing greenhouse gas emissions and promoting sustainable development in the management of environmental contamination. This trend is within the broader context of sustainable remediation strategies that balance environmental, economic, and social aspects. This article critically reviewed existing literature to evaluate and compare various low-carbon remediation methods, such as bioremediation, phytoremediation, in situ chemical oxidation, soil vapour extraction, and electrokinetic remediation, to identify suitable techniques for the remediation of oil-contaminated sites in the Niger Delta region of Nigeria. We analysed the UK sustainable remediation frameworks (SuRF-UK) to glean lessons for the Nigerian context. Our findings indicate that bioremediation and phytoremediation are particularly promising low-carbon remediation technologies for the Niger Delta region due to their cost-effectiveness and adaptability to local conditions. We proposed a framework that deeply considers opportunities for achieving multiple goals including effective remediation and limited greenhouse gas emissions while returning net social and economic benefit to local communities. The proposed framework will help decision makers to implement effective remediation technologies that meet sustainability indices, integrates emissions considerations return net environmental benefit to local communities. There is a need for policymakers to establish and enforce policies and regulations that support sustainable remediation practises, build the capacity of stakeholders, invest in research and development, and promote collaboration among stakeholders to create a regulatory environment that supports sustainable remediation practises and promotes environmental sustainability in the region. This study provides insights for achieving low-carbon remediation in regions addressing land contamination by different contaminants and facilitates the adoption of remediation technologies that consider contextual socio-economic and environmental indices for sustainable development.
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Affiliation(s)
| | - Kabari Sam
- School of the Environment, Geography and Geosciences, University of Portsmouth, PO1 3QL, UK
| | - Pablo Campo
- School of Water Energy and Environment, Cranfield University, MK430AL, UK
| | - Frederic Coulon
- School of Water Energy and Environment, Cranfield University, MK430AL, UK.
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Onyena AP, Nkwoji JA, Chukwu LO, Walker TR, Sam K. Risk assessment of sediment PAH, BTEX, and emerging contaminants in Chanomi Creek Niger Delta, Nigeria. Environ Monit Assess 2023; 195:1080. [PMID: 37615789 DOI: 10.1007/s10661-023-11703-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Accepted: 08/08/2023] [Indexed: 08/25/2023]
Abstract
This study assessed the levels of polycyclic aromatic hydrocarbons (PAHs), benzene, toluene, ethylbenzene, and xylene (BTEX), and emerging contaminants in Chanomi Creek. Sediment samples were collected between March 2019 and July 2020 to evaluate the concentrations of PAH, BTEX, and emerging contaminants using GC-MS and GC-FID with Headspace extraction. Results indicated mean PAH concentrations were 22.691 ± 15.09 µg/kg. The highest individual PAH concentrations were fluorene (7.085 µg/kg), naphthalene (4.517 µg/kg), and phenanthrene (3.081 µg/kg). Carbazole (0.828 µg/kg) was discovered as a novel environmental toxin with dioxin-like toxicity and widespread prevalence in sediments. The most common congener (25%) was ethylbenzene, followed by toluene and ortho- and meta-xylene (21%) and benzene (13%). The analysis of diagnostic ratios revealed that the main factors responsible for the presence of PAHs in the study area are the residential use of firewood, emissions from industrial activities, bush burning, and petroleum slicks. The risk assessment indicated that most PAHs exceeded the permissible risk quotient values, suggesting a moderate to high ecological risk. However, cutaneous exposure to PAHs and BTEX was found to have minimal impact on human health, with no significant hazards identified in adults and children. Nevertheless, the study revealed low cancer risks associated with PAH and BTEX compounds for both age groups. The continued discharge of PAHs and BTEX compounds into Chanomi Creek could have significant long-term negative effects on human and aquatic health. Thus, contamination risk awareness programs and the development of stringent contextual thresholds for identified contaminants could enhance environmental and public health protection.
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Affiliation(s)
- Amarachi P Onyena
- Department of Marine Sciences, Faculty of Science, University of Lagos, Lagos State, Nigeria.
- Department of Marine Environment and Pollution Control, Faculty of Marine Environmental Management, Nigeria Maritime University, Okerenkoko, Delta State, Nigeria.
| | - Joseph A Nkwoji
- Department of Marine Sciences, Faculty of Science, University of Lagos, Lagos State, Nigeria
| | - Lucian O Chukwu
- Department of Marine Sciences, Faculty of Science, University of Lagos, Lagos State, Nigeria
| | - Tony R Walker
- School for Resource and Environmental Studies, Dalhousie University, Halifax, Canada
| | - Kabari Sam
- Department of Marine Environment and Pollution Control, Faculty of Marine Environmental Management, Nigeria Maritime University, Okerenkoko, Delta State, Nigeria
- School of Environment, Geography and Geoscience, University of Portsmouth, Burnaby Road, Portsmouth, PO1 3QL, UK
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Chris DI, Onyena AP, Sam K. Evaluation of human health and ecological risk of heavy metals in water, sediment and shellfishes in typical artisanal oil mining areas of Nigeria. Environ Sci Pollut Res Int 2023; 30:80055-80069. [PMID: 37286839 DOI: 10.1007/s11356-023-27932-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 05/22/2023] [Indexed: 06/09/2023]
Abstract
Heavy metal contamination in water and sediment is a serious concern in nations that depend heavily on natural resources such as Nigeria. In most coastal communities around oil mining areas in Nigeria, drinking water quality, staple food, and livelihoods are primarily dependent on ecological systems and marine resources (e.g., fish). Thus, humans and other receptors are exposed to heavy metal risks through ingestion and dermal contact. This research evaluated the potential ecological risks of heavy metals including Cadmium (Cd), Chromium (Cr), Nickel (Ni), and Lead (Pb) in water, sediments, and shellfishes (Callinectes amnicola, Uca tangeri, Tympanotonus fuscatus, Peneaus monodon) along the Opuroama Creek in Niger Delta, Nigeria. The concentrations of heavy metals were measured in three stations using the Atomic Absorption Spectrophotometer and their relative ecological (geo-accumulation index and contamination factor) and human health risk (hazard index and hazard quotient) analysed. The toxicity response indices of the heavy metals indicate that the sediments pose significant ecological risk particularly with Cd. None of the three exposure pathways to heavy metals in the shellfish muscles and age groups pose a non-carcinogenic risk. Total Cancer Risk values for Cd and Cr exceeded the acceptable range (10-6 to 10-4) established by USEPA in children and adults, raising concerns of potential cancer risks following exposure to these metals in the area. This established a significant possibility of heavy metal risks to public health and marine organisms. The study recommends conducting in-depth health analysis and reducing oil spills while providing sustainable livelihoods to the local population.
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Affiliation(s)
| | - Amarachi Paschaline Onyena
- Department of Marine Environment and Pollution Control, Nigeria Maritime University, Okerenkoko, Warri, Nigeria.
| | - Kabari Sam
- Department of Marine Environment and Pollution Control, Nigeria Maritime University, Okerenkoko, Warri, Nigeria
- School of Environment, Geography and Geoscience, University of Portsmouth, Burnaby Road, Portsmouth, PO1 3QL, UK
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Sam K, Onyena AP, Zabbey N, Odoh CK, Nwipie GN, Nkeeh DK, Osuji LC, Little DI. Prospects of emerging PAH sources and remediation technologies: insights from Africa. Environ Sci Pollut Res Int 2023; 30:39451-39473. [PMID: 36773255 DOI: 10.1007/s11356-023-25833-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 02/06/2023] [Indexed: 02/12/2023]
Abstract
Remediation of polluted environmental media is critical to realization of the goals of the United Nations Decade on Ecosystem Restoration (UNDER) project. Many natural-resource dependent economies in Africa are characterized by numerous contaminated sites resulting from conventional and artisanal natural-resource mining. Alongside these extractive activities, there are refining, processing, and power plant operations, agriculture, urban, and infrastructure developments that contribute to increased discharges of toxins into the environment, particularly polycyclic aromatic hydrocarbons (PAHs), which are carcinogenic in nature. As a result, human and environmental receptors (i.e., air, water, soil, and biota) face increasing risk of exposure to higher concentrations of PAH. Evidence exists of widespread PAH contamination and in some instances where corrective action has been taken, residual contaminant levels exceeding regulatory thresholds remain in the environment due to the use of inappropriate and unsustainable remedial methods. Considering the long-term harmful effects of PAH on human and ecosystem health, land use, and the complexity of Africa's environmental deterioration, it is essential to explore remediation strategies that benefit both the environment and the economy. This review examined the status, opportunities, and challenges related to the application of emerging green technologies to remediate PAH-contaminated sites in five African countries (South Africa, Nigeria, Angola, Egypt, and Kenya). This paper concludes that bioremediation presents a sustainable option, considering its low net emissions and environmental footprints, and its low economic cost to Africa's poor communities and overburdened economy. However, an integration of biological and physico-chemical approaches could address various compounds and concentrations of PAH contamination.
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Affiliation(s)
- Kabari Sam
- School of Environment, Geography and Geoscience, University of Portsmouth, University House, Winston Churchill Ave, Portsmouth, PO1 2UP, UK.,Department of Marine Environment and Pollution Control, Faculty of Marine Environmental Management, Nigeria Maritime University, Okerenkoko, Delta State, Nigeria
| | - Amarachi P Onyena
- Department of Marine Environment and Pollution Control, Faculty of Marine Environmental Management, Nigeria Maritime University, Okerenkoko, Delta State, Nigeria.
| | - Nenibarini Zabbey
- Department of Fisheries, Faculty of Agriculture, University of Port Harcourt, East-West Road, PMB 5323, Choba, Port Harcourt, Rivers State, Nigeria.,Environment and Conservation Unit, Centre for Environment, Human Rights and Development (CEHRD), D-Line, Port Harcourt, Rivers State, Nigeria
| | - Chuks K Odoh
- Division of Biotechnology, Dalian Institute of Chemical Physics, CAS, Dalian, 116023, China
| | - Goodluck N Nwipie
- Department of Fisheries, Faculty of Agriculture, University of Port Harcourt, East-West Road, PMB 5323, Choba, Port Harcourt, Rivers State, Nigeria
| | - Dumbari K Nkeeh
- Department of Environmental Technology and Management, World Bank Africa Centre of Excellence, Centre for Oilfield Chemicals Research, University of Port Harcourt, Choba, P.M.B.5323, Port Harcourt, Rivers State, Nigeria
| | - Leo C Osuji
- Petroleum Chemistry Research Group, Department of Pure and Industrial Chemistry, University of Port Harcourt, Choba, P.M.B 5323, Port Harcourt, Nigeria
| | - David I Little
- Environmental Consultancy, Swavesey, Cambridgeshire, Cambridge, CB24 4RL, UK
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Nwankwegu AS, Zhang L, Xie D, Onwosi CO, Muhammad WI, Odoh CK, Sam K, Idenyi JN. Bioaugmentation as a green technology for hydrocarbon pollution remediation. Problems and prospects. J Environ Manage 2022; 304:114313. [PMID: 34942548 DOI: 10.1016/j.jenvman.2021.114313] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Revised: 10/26/2021] [Accepted: 12/13/2021] [Indexed: 06/14/2023]
Abstract
Environmental pollution mitigation measure involving bioremediation technology is a sustainable intervention for a greener ecosystem biorecovery, especially the obnoxious hydrocarbons, xenobiotics, and other environmental pollutants induced by anthropogenic stressors. Several successful case studies have provided evidence to this paradigm including the putative adoption that the technology is eco-friendly, cost-effective, and shows a high tendency for total contaminants mineralization into innocuous bye-products. The present review reports advances in bioremediation, types, and strategies conventionally adopted in contaminant clean-up. It identified that natural attenuation and biostimulation are faced with notable limitations including the poor remedial outcome under the natural attenuation system and the residual contamination occasion following a biostimulation operation. It remarks that the use of genetically engineered microorganisms shows a potentially promising insight as a prudent remedial approach but is currently challenged by few ethical restrictions and the rural unavailability of the technology. It underscores that bioaugmentation, particularly the use of high cell density assemblages referred to as microbial consortia possess promising remedial prospects thus offers a more sustainable environmental security. The authors, therefore, recommend bioaugmentation for large scale contaminated sites in regions where environmental degradation is commonplace.
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Affiliation(s)
- Amechi S Nwankwegu
- College of Resources and Environment, Southwest University, 1 Tiansheng Road, Beibei District, Chongqing, 400716, China; Organization of African Academic Doctors, Off Kamiti Road, P.O. Box 25305-00100, Nairobi, Kenya.
| | - Lei Zhang
- College of Resources and Environment, Southwest University, 1 Tiansheng Road, Beibei District, Chongqing, 400716, China
| | - Deti Xie
- College of Resources and Environment, Southwest University, 1 Tiansheng Road, Beibei District, Chongqing, 400716, China
| | - Chukwudi O Onwosi
- Department of Microbiology, Faculty of Biological Sciences, University of Nigeria, Nsukka, Enugu State, Nigeria
| | - Wada I Muhammad
- Organization of African Academic Doctors, Off Kamiti Road, P.O. Box 25305-00100, Nairobi, Kenya; College of Water Conservancy, Hohai University, No.1 Xikang Road, Gulou District, Nanjing, 210098, China
| | - Chuks K Odoh
- Organization of African Academic Doctors, Off Kamiti Road, P.O. Box 25305-00100, Nairobi, Kenya; Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Beijing, China
| | - Kabari Sam
- Faculty of Environmental Management, Department of Marine Environment and Pollution Control, Nigeria Maritime University, Okerenkoko, Delta State, Nigeria
| | - John N Idenyi
- Department of Biotechnology, Ebonyi State University Abakaliki, Nigeria
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Nwipie GN, Hart AI, Zabbey N, Sam K, Prpich G, Kika PE. Recovery of infauna macrobenthic invertebrates in oil-polluted tropical soft-bottom tidal flats: 7 years post spill. Environ Sci Pollut Res Int 2019; 26:22407-22420. [PMID: 31154642 DOI: 10.1007/s11356-019-05352-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 05/01/2019] [Indexed: 06/09/2023]
Abstract
Coastal oil spills constitute significant threat to biotic energy distribution, and biodiversity integrity amongst others. This study monitored the recovery of low-intertidal, soft-bottom infauna macrobenthic invertebrates in Bodo Creek intermittently over a 7-year period post oil spill. Samples were taken twice a month (spring and neap low tides) for 6 months (September 2015-February 2016) at sites previously studied (pre-spill baseline studies, 3-year and 5-year post-spill studies) for the effects of oil pollution using the same sampling methods used during initial studies of the same area. Comparatively, the initial studies reported Polychaeta as the dominant class against the dominant Crustacea reported in this 7-year post-spill study, indicating a change in the community structure of the study area. Infauna macro-invertebrate communities recorded showed an improvement (that is, increased species richness and number of individuals) over the initial 3-year and 5-year post-spill studies. However, relating the results to the initial baseline pre-spill studies, an annual average of 9.7% recovery rate was observed. Analysis of results showed that the total hydrocarbon content (THC) of the sediment remained high (90.08-12,184 mg/kg) but was markedly lower than levels observed during the initial post-spill study (6422-7186 mg/kg). Tidal flushing and biodegradation processes were deemed responsible for the reduction in THC. This study provides a rare dataset that describes the effects of oil pollution on a previously near-pristine estuarine environment in the tropics.
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Affiliation(s)
- Goodluck Nakaima Nwipie
- Department of Fisheries, Faculty of Agriculture, University of Port Harcourt, PMB 5323, East-West Road, Choba, Port Harcourt, Rivers State, Nigeria
| | - Aduabobo Ibitoru Hart
- Department of Animal and Environmental Biology, Faculty of Science, University of Port Harcourt, Port Harcourt, Nigeria
| | - Nenibarini Zabbey
- Department of Fisheries, Faculty of Agriculture, University of Port Harcourt, PMB 5323, East-West Road, Choba, Port Harcourt, Rivers State, Nigeria
- Environment and Conservation Unit, Centre for Environment, Human Rights and Development, Legacy Centre, Abuja Lane, Port Harcourt, Nigeria
| | - Kabari Sam
- Environment and Conservation Unit, Centre for Environment, Human Rights and Development, Legacy Centre, Abuja Lane, Port Harcourt, Nigeria.
- Department of Marine Environment and Pollution Control, Faculty of Environmental Management, Nigeria Maritime University, Okerenkoko, Warri, Delta State, Nigeria.
| | - George Prpich
- Department of Chemical Engineering, University of Virginia, Charlottesville, USA
| | - Philomina Ehiedu Kika
- Department of Animal and Environmental Biology, Faculty of Science, University of Port Harcourt, Port Harcourt, Nigeria
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Odoh CK, Zabbey N, Sam K, Eze CN. Status, progress and challenges of phytoremediation - An African scenario. J Environ Manage 2019; 237:365-378. [PMID: 30818239 DOI: 10.1016/j.jenvman.2019.02.090] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2018] [Revised: 02/17/2019] [Accepted: 02/19/2019] [Indexed: 05/21/2023]
Abstract
Environmental pollution occasioned by artisanal activities and technical failures at exploration sites has affected mostly oil producing and other mineral resources mining regions in developed and developing nations. As conventional techniques of remediation seem to be progressively unreliable and inefficient, contaminated land management experts have adopted a plant-based technology described as 'phytoremediation' for effective detoxification and removal of contaminants in substrate environmental media (soil and sediment). This technique, has gained public acceptance because of its aesthetic, eco-friendly, solar energy driven and low cost attributes. With complexity of environmental pollution in Africa, identification of appropriate remediation approach that deliver net environmental benefit and economic profit to the society is vital, while also focusing on the exploitation of plants genetic tools for more clarity on phyto tolerance, uptake and translocation of pollutants. In this article, we reviewed the status, progress and challenges of phytoremediation in selected African countries (South Africa, Nigeria, Tanzania, Zambia, Egypt and Ghana), the ecological impact of the pollutants, phytoremediation strategies and the possible plants of choice. Besides highlighting the support roles played by soil fauna and flora, the fate of harvested biomass/dieback and its future prospects are also discussed. We further explored the factors challenging phytoremediation progress in Africa, amidst its promising potentials and applicability for sustainable ecosystem management paradigm.
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Affiliation(s)
- Chuks Kenneth Odoh
- Department of Microbiology, University of Nigeria, Nsukka, 410001, Enugu State, Nigeria
| | - Nenibarini Zabbey
- Department of Fisheries, Faculty of Agriculture, University of Port Harcourt, PMB, 5323, East-West Road, Choba, Rivers State, Nigeria; Environment and Conservation Unit, Centre for Environment, Human Rights and Development (CEHRD), Legacy Centre, 6 Abuja Lane, D-Line, Port Harcourt, Rivers State, Nigeria
| | - Kabari Sam
- Environment and Conservation Unit, Centre for Environment, Human Rights and Development (CEHRD), Legacy Centre, 6 Abuja Lane, D-Line, Port Harcourt, Rivers State, Nigeria; Department of Marine Environment and Pollution Control, Faculty of Marine Environmental Management, Nigeria Maritime University, Warri, Delta State, Nigeria.
| | - Chibuzor Nwadibe Eze
- Department of Microbiology, University of Nigeria, Nsukka, 410001, Enugu State, Nigeria
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McKetton L, Venkatraghavan L, Rosen C, Mandell DM, Sam K, Sobczyk O, Poublanc J, Gray E, Crawley A, Duffin J, Fisher JA, Mikulis DJ. Improved White Matter Cerebrovascular Reactivity after Revascularization in Patients with Steno-Occlusive Disease. AJNR Am J Neuroradiol 2018; 40:45-50. [PMID: 30573457 DOI: 10.3174/ajnr.a5912] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Accepted: 10/08/2018] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE One feature that patients with steno-occlusive cerebrovascular disease have in common is the presence of white matter (WM) lesions on MRI. The purpose of this study was to evaluate the effect of direct surgical revascularization on impaired WM cerebrovascular reactivity in patients with steno-occlusive disease. MATERIALS AND METHODS We recruited 35 patients with steno-occlusive disease, Moyamoya disease (n = 24), Moyamoya syndrome (n = 3), atherosclerosis (n = 6), vasculitis (n = 1), and idiopathic stenosis (n = 1), who underwent unilateral brain revascularization using a direct superficial temporal artery-to-MCA bypass (19 women; mean age, 45.8 ± 16.5 years). WM cerebrovascular reactivity was measured preoperatively and postoperatively using blood oxygen level-dependent (BOLD) MR imaging during iso-oxic hypercapnic changes in end-tidal carbon dioxide and was expressed as %Δ BOLD MR signal intensity per millimeter end-tidal partial pressure of CO2. RESULTS WM cerebrovascular reactivity significantly improved after direct unilateral superficial temporal artery-to-middle cerebral artery (STA-MCA) bypass in the revascularized hemisphere in the MCA territory (mean ± SD, -0.0005 ± 0.053 to 0.053 ± 0.046 %BOLD/mm Hg; P < .0001) and in the anterior cerebral artery territory (mean, 0.0015 ± 0.059 to 0.021 ± 0.052 %BOLD/mm Hg; P = .005). There was no difference in WM cerebrovascular reactivity in the ipsilateral posterior cerebral artery territory nor in the vascular territories of the nonrevascularized hemisphere (P < .05). CONCLUSIONS Cerebral revascularization surgery is an effective treatment for reversing preoperative cerebrovascular reactivity deficits in WM. In addition, direct-STA-MCA bypass may prevent recurrence of preoperative symptoms.
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Affiliation(s)
- L McKetton
- From the Division of Neuroradiology, Joint Department of Medical Imaging (L.M., C.R., D.M.M., K.S., O.S., J.P., E.G., A.C., D.J.M.)
| | - L Venkatraghavan
- Department of Anesthesia and Pain Management (L.V., J.A.F.), University Health Network, Toronto, Ontario, Canada
| | - C Rosen
- From the Division of Neuroradiology, Joint Department of Medical Imaging (L.M., C.R., D.M.M., K.S., O.S., J.P., E.G., A.C., D.J.M.)
| | - D M Mandell
- From the Division of Neuroradiology, Joint Department of Medical Imaging (L.M., C.R., D.M.M., K.S., O.S., J.P., E.G., A.C., D.J.M.)
| | - K Sam
- From the Division of Neuroradiology, Joint Department of Medical Imaging (L.M., C.R., D.M.M., K.S., O.S., J.P., E.G., A.C., D.J.M.).,Russell H. Morgan Department of Radiology and Radiological Science (K.S.), John Hopkins School of Medicine, Baltimore, Maryland
| | - O Sobczyk
- From the Division of Neuroradiology, Joint Department of Medical Imaging (L.M., C.R., D.M.M., K.S., O.S., J.P., E.G., A.C., D.J.M.)
| | - J Poublanc
- From the Division of Neuroradiology, Joint Department of Medical Imaging (L.M., C.R., D.M.M., K.S., O.S., J.P., E.G., A.C., D.J.M.)
| | - E Gray
- From the Division of Neuroradiology, Joint Department of Medical Imaging (L.M., C.R., D.M.M., K.S., O.S., J.P., E.G., A.C., D.J.M.)
| | - A Crawley
- From the Division of Neuroradiology, Joint Department of Medical Imaging (L.M., C.R., D.M.M., K.S., O.S., J.P., E.G., A.C., D.J.M.)
| | - J Duffin
- Department of Physiology (J.D., J.A.F.).,Institute of Medical Sciences (J.D., J.A.F., D.J.M.), University of Toronto, Toronto, Ontario, Canada
| | - J A Fisher
- Department of Anesthesia and Pain Management (L.V., J.A.F.), University Health Network, Toronto, Ontario, Canada.,Department of Physiology (J.D., J.A.F.).,Institute of Medical Sciences (J.D., J.A.F., D.J.M.), University of Toronto, Toronto, Ontario, Canada
| | - D J Mikulis
- From the Division of Neuroradiology, Joint Department of Medical Imaging (L.M., C.R., D.M.M., K.S., O.S., J.P., E.G., A.C., D.J.M.) .,Institute of Medical Sciences (J.D., J.A.F., D.J.M.), University of Toronto, Toronto, Ontario, Canada
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Sam K, Zabbey N. Contaminated land and wetland remediation in Nigeria: Opportunities for sustainable livelihood creation. Sci Total Environ 2018; 639:1560-1573. [PMID: 29929319 DOI: 10.1016/j.scitotenv.2018.05.266] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 05/16/2018] [Accepted: 05/22/2018] [Indexed: 06/08/2023]
Abstract
The Niger Delta region of Nigeria is one of the most crude oil impacted deltas globally. The region has experienced over five decades of oil related contamination of the total environment (air, soil, water and biota). In 2011, UNEP released a seminal report on oil impact on Ogoniland environments, which up scaled demands for urgent clean up and restoration of degraded bio-resource rich environments of the Niger Delta, starting from Ogoniland. The Nigerian Government demonstrated renewed political will to remediate contaminated sites in Ogoniland with a launch of the clean-up exercise in June 2016. Stakeholders' expectations from the clean-up include not only environmental remediation but also restoration and creation of sustainable livelihood opportunities to reduce poverty in the region. Most studies have focused on the environmental restoration aspect and identified bioremediation as the likely appropriate remediation approach for Ogoniland, given its low environmental footprints, and low-cost burden on the weak and overstretched economy of Nigeria. This study mapped opportunities for sustainable livelihood creation during the Ogoniland remediation and restoration exercise. Given the value chain of bioremediation and its ancillary activities, the study analysed opportunities and mechanisms for skilled and unskilled job creation and prospects for sustainable livelihoods and knock-on effects. It is anticipated that the clean-up process would lead to economic prosperity and mitigate resource-driven conflicts in the Niger Delta. The study provides an exemplar for waste-to-wealth transformation in regions where natural resource mining has impacted communities, and has dislocated local economies and age-old livelihood structures.
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Affiliation(s)
- K Sam
- Environment and Conservation Unit, Centre for Environment, Human Rights and Development, Legacy Centre, Abuja Lane, Port Harcourt, Nigeria.
| | - N Zabbey
- Environment and Conservation Unit, Centre for Environment, Human Rights and Development, Legacy Centre, Abuja Lane, Port Harcourt, Nigeria; Department of Fisheries, Faculty of Agriculture, University of Port Harcourt, PMB 5323, East-West Road, Choba, Rivers State, Nigeria
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Benveniste APA, Ebuoma LO, Jonna A, Sam K, Severs FJ, Roark A, Sepulveda KA, Tamara OP, Sedgwick EE. Abstract P4-02-13: Can background parenchymal enhancement (BPE) predict the chance of multicentric/ bilateral breast cancer on staging breast MRI? Cancer Res 2018. [DOI: 10.1158/1538-7445.sabcs17-p4-02-13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Purpose: Can background parenchymal enhancement (BPE) predict the chance of multicentric/ bilateral breast cancer on staging Breast MRI?
Materials and Methods: Retrospective review of women diagnosed with breast cancer who underwent a breast MRI for staging of disease was performed at a single institution from October 2012 to September 2015.
Results: Breast MRI for staging was done for 435 patients diagnosed with breast cancer. Ages ranging from 24 to 86 years old (median, 52 years); sizes ranging from 0.5 to 13.5 cm (mean, 3.5 cm). 29 patients (7 %) had biopsy-proven second tumors in the same breast but different quadrant as the primary tumor or in the contralateral breast. From the 435 patients, 304 had minimal/ mild BPE and 103 had moderate/marked BPE (28 missing). Of the patients with an invasive primary cancer and a second tumor in the same breast but different quadrant as the primary tumor or in the contralateral breast, 12 of 29 patients had discordance in subtypes between the primary and secondary tumors (41%) and 17 of 29 had concordance in the subtypes between the primary and secondary tumors (59%). 6.3% (19 out 304) of patients with minimal/ mild BPE had multicentric /bilateral disease and 9.7% (10 out 103) of patients with moderate/ marked BPE had multicentric/ bilateral breast cancer.
Conclusion: 435 patients with recent diagnosis of breast cancer who underwent staging breast MRI for diagnosis of additional sites of disease, 7% was diagnosed with an additional site of cancer. From these group of patients, approximately 6% had other site of disease among patients who had minimal/ mild BPE in the breast MRI versus 10% of patients with moderate/marked BPE. BPE may play a role in the setting of multicentric/ bilateral breast cancer.
Citation Format: Benveniste APA, Ebuoma LO, Jonna A, Sam K, Severs Jr. FJ, Roark A, Sepulveda KA, Tamara O-P, Sedgwick EE. Can background parenchymal enhancement (BPE) predict the chance of multicentric/ bilateral breast cancer on staging breast MRI? [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-02-13.
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Affiliation(s)
| | - LO Ebuoma
- Baylor College of Medicine, Houston, TX
| | - A Jonna
- Baylor College of Medicine, Houston, TX
| | - K Sam
- Baylor College of Medicine, Houston, TX
| | - FJ Severs
- Baylor College of Medicine, Houston, TX
| | - A Roark
- Baylor College of Medicine, Houston, TX
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Zabbey N, Sam K, Onyebuchi AT. Remediation of contaminated lands in the Niger Delta, Nigeria: Prospects and challenges. Sci Total Environ 2017; 586:952-965. [PMID: 28214111 DOI: 10.1016/j.scitotenv.2017.02.075] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 02/08/2017] [Accepted: 02/08/2017] [Indexed: 06/06/2023]
Abstract
Contamination of the total environment (air, soil, water and biota) by crude oil has become a paramount interest in the Niger Delta region of Nigeria. Studies have revealed variable impacts of oil toxicity on the environment and exposed populations. The revelation gained much international attention in 2011 with the release of Environmental Assessment of Ogoniland report by the United Nations Environment Programme (UNEP). This has up scaled local and international pressures for urgent clean-up and restoration of degraded bio-resource rich environments of the Niger Delta, starting from Ogoniland. Previous remediation attempts in the area had failed due to erroneous operational conclusions (such as conclusions by oil industry operators that the Niger Delta soil is covered by a layer of clay and as such oil percolation remains within the top soil and makes remediation by enhanced natural attenuation (RENA) suitable for the region) and the adoption of incompatible and ineffective approaches (i.e. RENA) for the complex and dynamic environments. Perennial conflicts, poor regulatory oversights and incoherent standards are also challenges. Following UNEP recommendations, the Federal Government of Nigeria recently commissioned the clean-up and remediation of Ogoniland project; it would be novel and trend setting. While UNEP outlined some measures of contaminated land remediation, no specific approach was identified to be most effective for the Niger Delta region. Resolving the technical dilemma and identified social impediments is the key success driver of the above project. In this paper, we reviewed the socio-economic and ecological impacts of contaminated land in the Niger Delta region and the global state-of-the-art remediation approaches. We use coastal environment clean-up case studies to demonstrate the effectiveness of bioremediation (sometimes in combination with other technologies) for remediating most of the polluted sites in the Niger Delta. Bioremediation should primarily be the preferred option considering its low greenhouse gas and environmental footprints, and low-cost burden on the weak and overstretched economy of Nigeria.
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Affiliation(s)
- Nenibarini Zabbey
- Department of Fisheries, Faculty of Agriculture, University of Port Harcourt, PMB 5323, East-West Road, Choba, Rivers State, Nigeria; Environment and Conservation Unit, Center for Environment, Human Rights and Development (CEHRD), Legacy Centre, 6 Abuja Lane, D-Line, Port Harcourt, Rivers State, Nigeria
| | - Kabari Sam
- Cranfield University, School of Water, Energy, and Environment, College Road, Cranfield MK43 0AL, UK.
| | - Adaugo Trinitas Onyebuchi
- Environment and Conservation Unit, Center for Environment, Human Rights and Development (CEHRD), Legacy Centre, 6 Abuja Lane, D-Line, Port Harcourt, Rivers State, Nigeria
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Sam K, Coulon F, Prpich G. A multi-attribute methodology for the prioritisation of oil contaminated sites in the Niger Delta. Sci Total Environ 2017; 579:1323-1332. [PMID: 27916308 DOI: 10.1016/j.scitotenv.2016.11.126] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 11/17/2016] [Accepted: 11/18/2016] [Indexed: 06/06/2023]
Abstract
The Ogoniland region of the Niger Delta contains a vast number of sites contaminated with petroleum hydrocarbons that originated from Nigeria's active oil sector. The United Nations Environment Programme (UNEP) reported on this widespread contamination in 2011, however, wide-scale action to clean-up these sites has yet to be initiated. A challenge for decision makers responsible for the clean-up of these sites has been the prioritisation of sites to enable appropriate allocation of scarce resources. In this study, a risk-based multi-criteria decision analysis framework was used to prioritise high-risk sites contaminated with petroleum hydrocarbons in the Ogoniland region of Nigeria. The prioritisation method used a set of risk-based attributes that took into account chemical and ecological impacts, as well as socio-economic impacts, providing a holistic assessment of the risk. Data for the analysis was taken from the UNEP Environmental Assessment of Ogoniland, where over 110 communities were assessed for oil-contamination. Results from our prioritisation show that the highest-ranking sites were not necessarily the sites with the highest observed level of hydrocarbon contamination. This differentiation was due to our use of proximity as a surrogate measure for likelihood of exposure. Composite measures of risk provide a more robust assessment, and can enrich discussions about risk management and the allocation of resources for the clean-up of affected sites.
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Affiliation(s)
- Kabari Sam
- Cranfield University, School of Water, Energy, and Environment, College Road, Cranfield MK43 0AL, UK
| | - Frédéric Coulon
- Cranfield University, School of Water, Energy, and Environment, College Road, Cranfield MK43 0AL, UK
| | - George Prpich
- Cranfield University, School of Water, Energy, and Environment, College Road, Cranfield MK43 0AL, UK.
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Segar ST, Volf M, Zima Jnr J, Isua B, Sisol M, Sam L, Sam K, Souto-Vilarós D, Novotny V. Speciation in a keystone plant genus is driven by elevation: a case study in New Guinean Ficus. J Evol Biol 2016; 30:512-523. [DOI: 10.1111/jeb.13020] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 11/11/2016] [Accepted: 11/16/2016] [Indexed: 11/29/2022]
Affiliation(s)
- S. T. Segar
- Faculty of Science; University of South Bohemia; Ceske Budejovice Czech Republic
- Biology Centre CAS; Institute of Entomology; Ceske Budejovice Czech Republic
| | - M. Volf
- Faculty of Science; University of South Bohemia; Ceske Budejovice Czech Republic
- Biology Centre CAS; Institute of Entomology; Ceske Budejovice Czech Republic
| | - J. Zima Jnr
- Biology Centre CAS; Institute of Entomology; Ceske Budejovice Czech Republic
- Institute of Botany; Academy of Sciences of the Czech Republic; Třeboň Czech Republic
| | - B. Isua
- New Guinea Binatang Research Center; Madang Papua New Guinea
| | - M. Sisol
- New Guinea Binatang Research Center; Madang Papua New Guinea
| | - L. Sam
- Environmental Futures Research Institute; Griffith University; Brisbane Qld Australia
- Griffith School of Environment; Griffith University; Brisbane Qld Australia
| | - K. Sam
- Faculty of Science; University of South Bohemia; Ceske Budejovice Czech Republic
- Biology Centre CAS; Institute of Entomology; Ceske Budejovice Czech Republic
| | - D. Souto-Vilarós
- Faculty of Science; University of South Bohemia; Ceske Budejovice Czech Republic
- Biology Centre CAS; Institute of Entomology; Ceske Budejovice Czech Republic
| | - V. Novotny
- Faculty of Science; University of South Bohemia; Ceske Budejovice Czech Republic
- Biology Centre CAS; Institute of Entomology; Ceske Budejovice Czech Republic
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Sam K, Coulon F, Prpich G. Working towards an integrated land contamination management framework for Nigeria. Sci Total Environ 2016; 571:916-925. [PMID: 27443458 DOI: 10.1016/j.scitotenv.2016.07.075] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 07/11/2016] [Accepted: 07/11/2016] [Indexed: 06/06/2023]
Abstract
Over the past five decades, Nigeria has developed a number of contaminated land legislations to address the damage caused primarily by oil and gas exploitation activities. Within these legislations exists elements of risk assessment and risk-based corrective action. Despite this progress, we argue that contaminated land management approaches in Nigeria need further development to be able to integrate new scientific information, and to address environmental, economic, and social values. By comparison, advanced contaminated land regimes in the United Kingdom (UK), the Netherlands, Australia, New Zealand, and the United States of America (USA) apply a number of integrative approaches (e.g. sustainability appraisal, liability regime, funding mechanisms, technology demonstration) that enable them to meet the environmental, economic, and social needs of their populations. In comparison, Nigerian governance lacks many of these mechanisms and management of contaminated land is ad hoc. In this paper we propose an integrated risk assessment framework for Nigeria that incorporates the principles of sustainability and stakeholder engagement into the decision-making processes for contaminated land risk assessment and risk management. The integrated approach relies on transparency to promote acceptance and build trust in institutions, and uses stakeholder engagement to address data deficiencies. We conclude this paper with a roadmap for how Nigeria might implement such an integrative approach into their existing contaminated land regulatory system, as well as identify a series of policy priorities that should be addressed.
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Affiliation(s)
- Kabari Sam
- School of Water, Energy, and Environment, Cranfield University, College Road, Cranfield MK43 0AL, UK
| | - Frédéric Coulon
- School of Water, Energy, and Environment, Cranfield University, College Road, Cranfield MK43 0AL, UK
| | - George Prpich
- School of Water, Energy, and Environment, Cranfield University, College Road, Cranfield MK43 0AL, UK.
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Sam K, Crawley AP, Poublanc J, Conklin J, Sobczyk O, Mandell DM, Duffin J, Venkatraghavan L, Fisher JA, Black SE, Mikulis DJ. Vascular Dysfunction in Leukoaraiosis. AJNR Am J Neuroradiol 2016; 37:2258-2264. [PMID: 27492072 DOI: 10.3174/ajnr.a4888] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Accepted: 06/07/2016] [Indexed: 01/04/2023]
Abstract
BACKGROUND AND PURPOSE The pathogenesis of leukoaraiosis has long been debated. This work addresses a less well-studied mechanism, cerebrovascular reactivity, which could play a leading role in the pathogenesis of this disease. Our aim was to evaluate blood flow dysregulation and its relation to leukoaraiosis. MATERIALS AND METHODS Cerebrovascular reactivity, the change in the blood oxygen level-dependent 3T MR imaging signal in response to a consistently applied step change in the arterial partial pressure of carbon dioxide, was measured in white matter hyperintensities and their contralateral spatially homologous normal-appearing white matter in 75 older subjects (age range, 50-91 years; 40 men) with leukoaraiosis. Additional quantitative evaluation of regions of leukoaraiosis was performed by using diffusion (n = 75), quantitative T2 (n = 54), and DSC perfusion MRI metrics (n = 25). RESULTS When we compared white matter hyperintensities with contralateral normal-appearing white matter, cerebrovascular reactivity was lower by a mean of 61.2% ± 22.6%, fractional anisotropy was lower by 44.9 % ± 6.9%, and CBF was lower by 10.9% ± 11.9%. T2 was higher by 61.7% ± 13.5%, mean diffusivity was higher by 59.0% ± 11.7%, time-to-maximum was higher by 44.4% ± 30.4%, and TTP was higher by 6.8% ± 5.8% (all P < .01). Cerebral blood volume was lower in white matter hyperintensities compared with contralateral normal-appearing white matter by 10.2% ± 15.0% (P = .03). CONCLUSIONS Not only were resting blood flow metrics abnormal in leukoaraiosis but there is also evidence of reduced cerebrovascular reactivity in these areas. Studies have shown that reduced cerebrovascular reactivity is more sensitive than resting blood flow parameters for assessing vascular insufficiency. Future work is needed to examine the sensitivity of resting-versus-dynamic blood flow measures for investigating the pathogenesis of leukoaraiosis.
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Affiliation(s)
- K Sam
- From the Departments of Physiology (K.S., J.D., J.A.F.).,Division of Neuroradiology (K.S., A.P.C., J.P., J.C., O.S., D.M.M., D.J.M.), Joint Department of Medical Imaging, University Health Network, Toronto, Ontario, Canada
| | - A P Crawley
- Medical Imaging (A.P.C., D.J.M.), University of Toronto, Toronto, Ontario, Canada.,Division of Neuroradiology (K.S., A.P.C., J.P., J.C., O.S., D.M.M., D.J.M.), Joint Department of Medical Imaging, University Health Network, Toronto, Ontario, Canada
| | - J Poublanc
- Division of Neuroradiology (K.S., A.P.C., J.P., J.C., O.S., D.M.M., D.J.M.), Joint Department of Medical Imaging, University Health Network, Toronto, Ontario, Canada
| | - J Conklin
- Division of Neuroradiology (K.S., A.P.C., J.P., J.C., O.S., D.M.M., D.J.M.), Joint Department of Medical Imaging, University Health Network, Toronto, Ontario, Canada
| | - O Sobczyk
- Division of Neuroradiology (K.S., A.P.C., J.P., J.C., O.S., D.M.M., D.J.M.), Joint Department of Medical Imaging, University Health Network, Toronto, Ontario, Canada
| | - D M Mandell
- Division of Neuroradiology (K.S., A.P.C., J.P., J.C., O.S., D.M.M., D.J.M.), Joint Department of Medical Imaging, University Health Network, Toronto, Ontario, Canada
| | - J Duffin
- From the Departments of Physiology (K.S., J.D., J.A.F.).,Department of Anesthesiology (J.D., L.V., J.A.F.), University Health Network and The University of Toronto, Toronto, Ontario, Canada
| | - L Venkatraghavan
- Department of Anesthesiology (J.D., L.V., J.A.F.), University Health Network and The University of Toronto, Toronto, Ontario, Canada
| | - J A Fisher
- From the Departments of Physiology (K.S., J.D., J.A.F.).,Department of Anesthesiology (J.D., L.V., J.A.F.), University Health Network and The University of Toronto, Toronto, Ontario, Canada
| | - S E Black
- L.C. Campbell Cognitive Neurology Research Unit (S.E.B.), Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
| | - D J Mikulis
- Medical Imaging (A.P.C., D.J.M.), University of Toronto, Toronto, Ontario, Canada .,Division of Neuroradiology (K.S., A.P.C., J.P., J.C., O.S., D.M.M., D.J.M.), Joint Department of Medical Imaging, University Health Network, Toronto, Ontario, Canada
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Sobczyk O, Crawley AP, Poublanc J, Sam K, Mandell DM, Mikulis DJ, Duffin J, Fisher JA. Identifying Significant Changes in Cerebrovascular Reactivity to Carbon Dioxide. AJNR Am J Neuroradiol 2016; 37:818-24. [PMID: 26846924 DOI: 10.3174/ajnr.a4679] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 10/23/2015] [Indexed: 01/04/2023]
Abstract
BACKGROUND AND PURPOSE Changes in cerebrovascular reactivity can be used to assess disease progression and response to therapy but require discrimination of pathology from normal test-to-test variability. Such variability is due to variations in methodology, technology, and physiology with time. With uniform test conditions, our aim was to determine the test-to-test variability of cerebrovascular reactivity in healthy subjects and in patients with known cerebrovascular disease. MATERIALS AND METHODS Cerebrovascular reactivity was the ratio of the blood oxygen level-dependent MR imaging response divided by the change in carbon dioxide stimulus. Two standardized cerebrovascular reactivity tests were conducted at 3T in 15 healthy men (36.7 ± 16.1 years of age) within a 4-month period and were coregistered into standard space to yield voxelwise mean cerebrovascular reactivity interval difference measures, composing a reference interval difference atlas. Cerebrovascular reactivity interval difference maps were prepared for 11 male patients. For each patient, the test-retest difference of each voxel was scored statistically as z-values of the corresponding voxel mean difference in the reference atlas and then color-coded and superimposed on the anatomic images to create cerebrovascular reactivity interval difference z-maps. RESULTS There were no significant test-to-test differences in cerebrovascular reactivity in either gray or white matter (mean gray matter, P = .431; mean white matter, P = .857; paired t test) in the healthy cohort. The patient cerebrovascular reactivity interval difference z-maps indicated regions where cerebrovascular reactivity increased or decreased and the probability that the changes were significant. CONCLUSIONS Accounting for normal test-to-test differences in cerebrovascular reactivity enables the assessment of significant changes in disease status (stability, progression, or regression) in patients with time.
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Affiliation(s)
- O Sobczyk
- From the Institute of Medical Science (O.S., D.J.M., J.A.F.)
| | - A P Crawley
- Joint Department of Medical Imaging and the Functional Neuroimaging Laboratory (A.P.C., J.P., K.S., D.M.M., D.J.M.)
| | - J Poublanc
- Joint Department of Medical Imaging and the Functional Neuroimaging Laboratory (A.P.C., J.P., K.S., D.M.M., D.J.M.)
| | - K Sam
- Department of Physiology (K.S., J.D., J.A.F.), University of Toronto, Toronto, Canada Joint Department of Medical Imaging and the Functional Neuroimaging Laboratory (A.P.C., J.P., K.S., D.M.M., D.J.M.)
| | - D M Mandell
- Joint Department of Medical Imaging and the Functional Neuroimaging Laboratory (A.P.C., J.P., K.S., D.M.M., D.J.M.)
| | - D J Mikulis
- From the Institute of Medical Science (O.S., D.J.M., J.A.F.) Joint Department of Medical Imaging and the Functional Neuroimaging Laboratory (A.P.C., J.P., K.S., D.M.M., D.J.M.)
| | - J Duffin
- Department of Physiology (K.S., J.D., J.A.F.), University of Toronto, Toronto, Canada Department of Anaesthesia and Pain Management (J.D., J.A.F.), University Health Network, Toronto, Canada
| | - J A Fisher
- From the Institute of Medical Science (O.S., D.J.M., J.A.F.) Department of Physiology (K.S., J.D., J.A.F.), University of Toronto, Toronto, Canada Department of Anaesthesia and Pain Management (J.D., J.A.F.), University Health Network, Toronto, Canada
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Hou HM, Sam K, Hägg U, Rabie ABM, Bendeus M, Yam LYC, Ip MS. Long-term dentofacial changes in Chinese obstructive sleep apnea patients after treatment with a mandibular advancement device. Angle Orthod 2006; 76:432-40. [PMID: 16637723 DOI: 10.1043/0003-3219(2006)076[0432:ldcico]2.0.co;2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
The objective of this study was to evaluate long-term dentofacial changes in Chinese obstructive sleep apnea (OSA) patients treated with a mandibular advancement device (MAD). Lateral cephalograms in natural head posture were obtained from 67 consecutive OSA patients (mean age = 46.9 +/- 8.9 years) treated with an MAD. The cephalograms were obtained at start of treatment (T0), after 1 year (T1), 2 years (T2), and 3 years (T3) of treatment. The lateral cephalograms were digitized twice, and the average of two readings was used for statistical analyses. Small, but statistically significant changes occurred in some dentofacial variables. The lower anterior facial height steadily increased during the observation period, and this increase was significant for the T0-T1 and T1-T2 periods and marginally significant for the T2-T3 period. A significant increase in the mandibular plane angle was observed during the T0-T1 and T2-T3 periods only. Significant reductions in the overjet and overbite were observed for the T0-T1 period but not thereafter. Statistically significant dentofacial changes were observed in this study, but they were of small magnitude. The overjet and overbite changes observed mainly occurred at the initial stage of treatment.
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Affiliation(s)
- H M Hou
- Faculty of Dentistry, The University of Hong Kong, Prince Philip Dental Hospital, 34 Hospital Road, Hong Kong SAR, People's Republic of China
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Sam K, Lam B, Ooi CG, Cooke M, Ip MS. Effect of a non-adjustable oral appliance on upper airway morphology in obstructive sleep apnoea. Respir Med 2005; 100:897-902. [PMID: 16219453 DOI: 10.1016/j.rmed.2005.08.019] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2004] [Revised: 06/01/2005] [Accepted: 08/10/2005] [Indexed: 11/28/2022]
Abstract
BACKGROUND To evaluate the effect of oral appliance (OA) on upper airway morphology and its relationship with treatment response in subjects with obstructive sleep apnoea (OSA). METHODS Symptomatic OSA subjects were recruited. Non-adjustable OA was custom made. Variables examined at baseline and while wearing the device at 2 months included polysomnographic data, computed tomographic measurements of upper airway cross sectional area at level of velopharynx (VA) and hypopharynx (HA), upper airway volume, and cephalometric parameters. Treatment outcome was based on post-treatment apnoea-hypopnoea index (AHI). RESULTS Forty patients were recruited and 23 (7 women) completed the study. They were middle-aged (49, 40-58 years) (median, interquartile range) and overweight (BMI 26, 23.3-29.5 kg/m2), with moderate OSA (AHI 26.4, 14.1-36). The overall post treatment AHI was 8.4 (2.4-12.5), with 14 (61%) patients showing good response (AHI<10), and the other 9 patients showing moderate response (>50% reduction in AHI but still 10). OA decreased the cross-sectional area of the HA (P=0.046), showed a trend of decreasing the ratio of cross-sectional area of the HA to cross-sectional area of the VA (P=0.053) and significantly increased the overall upper airway volume (P=0.006, n=11). No significant relationship between upper airway parameters and treatment outcome was identified. CONCLUSIONS OA altered upper airway morphometry towards a profile consistent with decreased propensity to collapse, which may thus have contributed to improvement of OSA.
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Affiliation(s)
- K Sam
- Orthodontics, Faculty of Dentistry, University of Hong Kong, Hong Kong SAR, China
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Affiliation(s)
- C Xin
- School of Mathematical Sciences, Peking University.
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Sam K, Rabie AB, King NM. Orthodontic intrusion of periodontally involved teeth. J Clin Orthod 2001; 35:325-30. [PMID: 11475543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Affiliation(s)
- K Sam
- Faculty of Dentistry, University of Hong Kong, Prince Philip Dental Hospital, 34 Hospital Road, Hong Kong
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Sam K, Labrie F, Poirier D. N-Butyl-N-methyl-11-(3'-hydroxy-21', 17'-carbolactone-19'-nor-17'alpha-pregna-1',3', 5'(10')-trien-7'alpha-yl)-undecanamide: an inhibitor of type 2 17beta-hydroxysteroid dehydrogenase that does not have oestrogenic or androgenic activity. Eur J Med Chem 2000; 35:217-25. [PMID: 10758283 DOI: 10.1016/s0223-5234(00)00124-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
It is well known that 17beta-hydroxysteroid dehydrogenases (17beta-HSDs) play a key role in the formation and inactivation, from circulating precursors, of several active androgens and oestrogens. These enzymes can thus regulate tumoural cell proliferation in androgen- and oestrogen-dependent cancers. Recently, we discovered that adding a spiro-gamma-lactone to the oestradiol nucleus results in a novel inhibitor of type 2 17beta-HSD, an enzyme that catalyses the interconversions between 4-androstene-3,17-dione and testosterone, and between oestrone and oestradiol. This finding motivated our introducing the spiro-gamma-lactone moiety onto an anti-oestrogenic nucleus. The N-butyl-N-methyl-11-(3'-hydroxy-21', 17'-carbolactone-19'-nor-17'alpha-pregna-1',3', 5'(10')-trien-7'alpha-yl)-undecanamide (4) was then efficiently synthesized and its biological activity was assessed in vitro. Despite the presence of a bulky alkylamide side chain, the spiro-gamma-lactone function conserved its ability to inhibit type 2 17beta-HSD (IC(50) = 0.35 and 0.25 microM, with and without side chain, respectively). Furthermore, the selective inhibition by lactone 4 toward type 2 17beta-HSD (microsomal fraction of human placenta) was demonstrated by the absence of inhibitory activity toward type 1 17beta-HSD (cytosolic fraction of human placenta). Cell proliferation assays indicated that compound 4 had no oestrogenic activity but did show anti-oestrogenic activity on ER(+) cell line ZR-75-1. No androgenic activity could be detected when assayed on the AR(+) cell line Shionogi either. Based on these facts, we report the synthesis of a new steroidal derivative, one that inhibits type 2 17beta-HSD while possessing anti-oestrogenic activity.
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Affiliation(s)
- K Sam
- Medicinal Chemistry Division, Laboratory of Molecular Endocrinology, Laval University Medical Research Center, Centre hospitalier universitaire de Québec and Laval University, 2705 Laurier Boulevard, Québec, Canada
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